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Central Anatolia is quiet in terms of seismic activity, and rarely earthquakes up to magnitude 5.6 occur in the inner part of the Anatolian block or Anatolian platelet. Southeast of Ankara, the capital city of Turkey, two earthquake sequences with maximum magnitude of 5.6 occurred in 2005 and 2007. We discuss these shallow crustal deformation in the Anatolian platelet, in the light of seismological data from these earthquakes (ML= 5.6) and their aftershocks. Following the earthquake of December 20, 2007 near Bala town, Ankara, we installed seven temporary stations in the first 24 hours to observe the aftershock activity and these operated for more than 2 months. Approximately 920 aftershocks with magnitudes 5.5>ML>0.8 were located precisely. This is the first well-observed earthquake activity in the Central Anatolian section of the Anatolian platelet. We also re-analyzed the 2005 Bala earthquake sequence. The distribution of the well-located aftershocks and the focal mechanism solutions of the December 20, 2007 event define NW-SE-oriented right-lateral strike-slip faulting on a possible weak zone, namely the Afşar fault zone, as a result of the internal deformation in the Anatolian platelet. Our analyses seem to indicate that the Bala earthquake sequences are probably related to increasing seismic activity, following devastating 1999 earthquakes in the Marmara region, to the west.

Seismic reflection data from target depths of several hundred metres have been acquired and processed as an aid for lignite exploration in the Miocene Soma Basin, western Turkey. An environmentally-friendly approach was followed by acquiring the data with mini-vibroseisseismic source along crooked lines, using available mountain/forest and village roads; quality control tests were conducted to determine optimal field parameters that would yield dataset with best signal-to-noise (SN) ratio prior to real data acquisition; and stratigraphic interfaces giving rise to reflection events in the seismic data were identified from the vertical seismic profiling (VSP). Stacked seismic sections were successfully correlated with geological cross-sections drawn based on available borehole data. Thus, it is shown that decreasing time and the cost for coal exploration is possible by utilising surface and VSP. Environment friendly approach of the seismic method applied in this study is also beneficial in regard to environmental concerns.

In this study, our primary objective is to understand CBM capacity of the Soma coal basin. For this reason, porosity of the coal samples must be determined. Usually, surface area and the porosity of the materials can be calculated through the N2 physical sorption experiment, in this method entire relative pressure range (10-8 to 1) can be analyzed without using high pressure equipments. However, for microporous materials like carbon materials and zeolites physical sorption occurs at very low relative pressure ranges (10-8 to 10-3) and experiments that are conducted with N2 are less reliable due to the low diffusion rate and adsorption equilibrium in the pores between 0,5 to 1 nm at 77 K. It is also known that specifically for carbon materials experiments that are conducted at low temperatures such as N2 sorption causes pore shrinkage that leads to the low sorption equilibrium.

A destructive earthquake (M-w = 6.1) occurred on the northeast end of the Palu segment of the East Anatolian Fault System (EAFS, eastern Turkey) on 8 March 2010. The spatial distribution of aftershocks suggests that the Palu segment does not terminate to the east of Palu town but extends in the N50 degrees E direction where it has produced a 30 km right stepover. Aftershock depths indicate a seismogenic brittle zone of about 15 km depth. The stress changes on the segments due to recorded events might have loaded more than 0.5 bars of stress on the NE end of the Palu segment and the SW end of the Goynuk segment. Therefore, a future earthquake on both segments may occur sooner than was expected before the occurrence of the Mw 6.1 earthquake on 8 March 2010. Citation: Tan, O., Z. Pabuccu, M. C. Tapirdamaz, S. Inan, S. Ergintav, H. Eyidogan, E. Aksoy, and F. Kuluozturk (2011), Aftershock study and seismotectonic implications of the 8 March 2010 Kovancilar (Elazig, Turkey) earthquake (M-W = 6.1), Geophys. Res. Lett., 38, L11304, doi:10.1029/2011GL047702.

To investigate the onshore/offshore structural framework of the northern shelf of the Sea of Marmara, a multidisciplinary study was carried out including multichannel and single-channel seismic reflection profiling, multibeam bathymetry sounding, side-scan sonar imaging on offshore as well as land studies for S-wave velocity estimation by passive and active array measurements and monitoring of block deformations by Global Positioning System (GPS). Based on the multidisciplinary data, possible interactions between landslides and active faulting have been reviewed and their possible relation to the North Anatolian Fault Zone (NAFZ) has been discussed.

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The Neogene Basins of Turkey contain as much as 9 billion tons of lignite-rank coal (Şengiller, 2001; Tuncah et al., 2002). The Miocene Soma Basin, a rift basin trending NE-SW (approximately 20 kilometers by 5 kilometers) in the Aegean Extensional Province (EAP) of Western Turkey, is estimated to contain. at the least one billion tons of lignite and about half of this reserve is present at depths greater than 600 m (Turkish Coal Enterprises, 2006). Miocene marlJlimestone units and Pliocene clastics and volcanic tuffs overlie the Miocene coals of the Soma basin. There are several coal seams in the basin but the most economical and thus target seam is known as KM2 with an average thickness of about 20 meter across the basin. In the Soma Basin, Turkish Coal Enterprises (00) has mined this KM2 seam by open cut coal mining and underground mining for several decades in the Northern and Central part of the basin, respectively. Recently, coal exploration activities have been extended to the Southern part of the basin by means of exploratory drillings. In order to aid fast and economical coal exploration activities of the Turkish Coal Enterprises (TKt), a colloborative work has been started for development of an integrated seismic method for coal exploration. The aim is to develop a practical seismic method for TKİ to apply in its exploration activities in other lignite coal basins of Turkey. The information gathered from tens of coal exploration borehole! already drilled in the study area will be used to calibrate the horizons to be mapped b) surface seismic and WVSP methods (Tselentis and Paraskevopoulos, 2002). Surface seismic data will be collected on roughly East-West and North-South oriented lines Furthermore, at the intersect of these lines borehole WVSP data will be collected. The seismic source for both surface and borehole WVSP seismic will be a mini-vibrator and the data will be collected contamporanously. The seismic study will be conductec between May and July 2010. Soon after, the seismic data processing work will be initiated.

The Neogene Basins of Turkey contain as much as 9 billion tons of lignite-rank coal (Sengiller, 2001; Tuncah et al., 2002). The Miocene Soma Basin, a rift basin trending NE-SW (approximately 20 kilometers by 5 kilometers) in the Aegean Extensional Province (EAP) of Western Turkey, is estimated to contain at the least one billion tons of lignite and about half of this reserve is present at depths greater than 600 m (Turkish Coal Enterprises, 2006). Miocene marillimestone units and Pliocene clastics and volcanic tuffs overlie the Miocene coals of the Soma basin. There are several coal seams in the basin but the most economical and thus target sean! is known as KM2 with an average thickness of about 20 meter across the basin. In the Soma Basin, Turkish Coal Enterprises (TKt) has mined this KM2 seam by open cut coal mining and underground mining for several decades in the Northern and Central part of the basin, respectively. Recently, coal exploration activities have been extended to the Southern part of the basin by means of exploratory drillings. Recently, coal exploration activities have been extended to the Southern part of the basin by means of exploratory drillings. In this context, two boreholes encountering a coal seam (KM2) up to 20 m thick were evaluated. The KM2 coal seam was encountered between 900 and 940 m depth in two boreholes drilled approximately I km apart. Wellhead gas content was measured on coal cores following the USBM method (Diamond and Levine, 1981). Additionally, coal was placed in hermetically sealed canister and desorbed gas was analyzed in laboratory for chemical composition (by FTIR gas analyzer) and 13C isotope (by Ge¬IRMS). Coal characterization was completed by means of Rock Eval (RE) Pyrolysis, Proximate and Ultimate analyses, as well as microscopic analyses for typing of macerals and vitrinite (hurninte) reflectance measurements. The wellhead gas content measurements (six. core measurements from two boreholes) indicate that as much as 4 m3 gas / ton coal is present in the coal recovered from 900 to 940 m below the surface. The rank of coal based on vitrinite (hurninte) reflectance measurements is lignite to sub-bituminous (0.40 to 0.45 % Ro); supported by RE Tmax values of 420 DC. TOC content of the coal samples vary between 53 to 73 %. The composition of the gas is dominantly methane (more than 99.4 %) and the l3cl2c isotope ratio of methane is 61 to 65 per mil. Considering the chemical composition of the gas and the del 13C isotope of the methane, the source of the coal gas is biogenic probably generated by bacteria. The maceral analyses show that coal samples on average contain more than 60 % huminite(vitrinite). Adsorption on the internal coal surface is considered as the primary mechanism of gas storage in coals and the surface area, which controls the gas adsorption capacity, is in general a function of the micro¬pore volume (Levy et al., 1997; Crosdale et al., 1998) which is known to be abundant in vitrinite maceral group. The vitrinite/hurninite masera1 content has positive correlation with gas sorption capacity (Levy et al., 1997); meaning that at a given pressure, the higher percentage of micro-pore dominated huminiteivitrinite the more gas adsorption capacity. In this context, the Miocene Soma lignites have good micro¬pore properties in respect to gas adsorption. Preliminary evaluation, based on limited analyses and results summarized above, on gas potential of the Miocene Soma Basin is encouraging, yet further investigations in the Soma Basin are underway by coal desorption testing of cores received from ongoing coal exploration boreholes.

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Central Anatolia is quiet in terms of seismic activity, and rarely earthquakes up to magnitude 5.6 occur in the inner part of the Anatolian block or Anatolian platelet. Southeast of Ankara, the capital city of Turkey, two earthquake sequences with maximum magnitude of 5.6 occurred in 2005 and 2007. We discuss these shallow crustal deformation in the Anatolian platelet, in the light of seismological data from these earthquakes (M(L) = 5.6) and their aftershocks. Following the earthquake of December 20, 2007 near Bala town, Ankara, we installed seven temporary stations in the first 24 hours to observe the aftershock activity and these operated for more than 2 months. Approximately 920 aftershocks with magnitudes 5.5>M(L)>0.8 were located precisely. This is the first well-observed earthquake activity in the Central Anatolian section of the Anatolian platelet. We also re-analyzed the 2005 Bala earthquake sequence. The distribution of the well-located aftershocks and the focal mechanism solutions of the December 20, 2007 event define NW-SE-oriented right-lateral strike-slip faulting on a possible weak zone, namely the Afsar fault zone, as a result of the internal deformation in the Anatolian platelet. Our analyses seem to indicate that the Bala earthquake sequences are probably related to increasing seismic activity, following devastating 1999 earthquakes in the Marmara region, to the west.

[1] Physical and chemical properties of warm and hot spring waters as well as soil radon concentrations were measured continuously during a 3-year period in the Marmara region; following the devastating I zmit earthquake of 17 August 1999 (Mw = 7.4). Promising and encouraging anomalies in ground radon emanation have been recorded and found to be closely related to seismic activity. The temporal and spatial variations in the soil radon data are presented. The earthquakes with magnitude >4 in the region were correlated with positive radon anomalies. Furthermore, during quiescence (absence of seismic activity) the radon data indicate random walk behavior of radon in soil and show Rayleigh-type probability density function (pdf), however, during the earthquake build-up period, the data show deviations from Rayleigh-type pdf. The radon positive anomalies indicate disturbance of the path of gas movement or gas release pattern prior to earthquakes. However, systematic and consistent anomalies in physical and/or chemical properties of the spring waters have not been detected for earthquakes occurring in the observation period (M < 5.3).